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The Kimban orogeny , also termed the Strangways orogeny, affected the Gawler Craton in what is now Australia between 1.73 and 1.69 billion years ago in the Proterozoic. As the most widespread orogenic event in the craton's evolution, the Kimban orogeny led to widely variable metamorphism included granulite and greenschist-grade on the sequence of metamorphic facies, preserved in the Tunkillia, Moody and Middlecamp rock suites. The Moody Suite formed late in the orogeny and was intruded with hornblende-rich granitoids and muscovite-rich leucogranites. [1]
The Congo Craton, covered by the Palaeozoic-to-recent Congo Basin, is an ancient Precambrian craton that with four others makes up the modern continent of Africa. These cratons were formed between about 3.6 and 2.0 billion years ago and have been tectonically stable since that time. All of these cratons are bounded by younger fold belts formed between 2.0 billion and 300 million years ago.
The Pan-African orogeny was a series of major Neoproterozoic orogenic events which related to the formation of the supercontinents Gondwana and Pannotia about 600 million years ago. This orogeny is also known as the Pan-Gondwanan or Saldanian Orogeny. The Pan-African orogeny and the Grenville orogeny are the largest known systems of orogenies on Earth. The sum of the continental crust formed in the Pan-African orogeny and the Grenville orogeny makes the Neoproterozoic the period of Earth's history that has produced most continental crust.
The Gawler Craton covers approximately 440,000 square kilometres of central South Australia. Its Precambrian crystalline basement crustal block was cratonised ca. 1550–1450 Ma. Prior to 1550 Ma the craton comprised a number of active Proterozoic orogenic belts extending back in time to at least 2450 Ma.
The Amazonian Craton is a geologic province located in South America. It occupies a large portion of the central, north and eastern part of the continent and represents one of Earth's largest cratonic regions. The Guiana Shield and Central Brazil Shield constitute respectively the northern and southern exhumed parts of the craton. Between the two shields lies the Amazon Rift, a zone of weakness within the craton. Smaller cratons of Precambrian rocks south of the Amazonian Shield are the Río de la Plata Craton and the São Francisco Craton, which lies to the east.
The Wyoming Craton is a craton in the west-central United States and western Canada – more specifically, in Montana, Wyoming, southern Alberta, southern Saskatchewan, and parts of northern Utah. Also called the Wyoming Province, it is the initial core of the continental crust of North America.
Laurentia or the North American Craton is a large continental craton that forms the ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of North America, although originally it also included the cratonic areas of Greenland and also the northwestern part of Scotland, known as the Hebridean Terrane. During other times in its past, Laurentia has been part of larger continents and supercontinents and consists of many smaller terranes assembled on a network of early Proterozoic orogenic belts. Small microcontinents and oceanic islands collided with and sutured onto the ever-growing Laurentia, and together formed the stable Precambrian craton seen today.
The Circum-Superior Belt is a widespread Paleoproterozoic large igneous province in the Canadian Shield of Northern, Western and Eastern Canada. It extends more than 3,400 km (2,100 mi) from northeastern Manitoba through northwestern Ontario, southern Nunavut to northern Quebec and into western Labrador. Igneous rocks of the Circum-Superior Belt are mafic-ultramafic in composition, deposited in the Labrador Trough near Ungava Bay, the Cape Smith Belt near the southern shore of Hudson Strait and along the eastern shore of Hudson Bay in its northern portion; the Thompson and Fox River belts in the northwest and the Marquette Range Supergroup in its southern portion. The Circum Superior Belt also hosts a rare example of Proterozoic Komatiite, in the Winnipegosis komatiite belt.
The West African Craton (WAC) is one of the five cratons of the Precambrian basement rock of Africa that make up the African Plate, the others being the Kalahari craton, Congo craton, Saharan Metacraton and Tanzania Craton. Cratons themselves are tectonically inactive, but can occur near active margins, with the WAC extending across 14 countries in Western Africa, coming together in the late Precambrian and early Palaeozoic eras to form the African continent. It consists of two Archean centers juxtaposed against multiple Paleoproterozoic domains made of greenstone belts, sedimentary basins, regional granitoid-tonalite-trondhjemite-granodiorite (TTG) plutons, and large shear zones. The craton is overlain by Neoproterozoic and younger sedimentary basins. The boundaries of the WAC are predominantly defined by a combination of geophysics and surface geology, with additional constraints by the geochemistry of the region. At one time, volcanic action around the rim of the craton may have contributed to a major global warming event.
This timeline of natural history summarizes significant geological and biological events from the formation of the Earth to the arrival of modern humans. Times are listed in millions of years, or megaanni (Ma).
The Saharan Metacraton is a large area of continental crust in the north-central part of Africa. Whereas a craton is an old and stable part of the lithosphere, the term "metacraton" is used to describe a craton that has been remobilized during an orogenic event, but where the characteristics of the original craton are still identifiable. The geology of the continent has only been partially explored, and other names have been used to describe the general area that reflect different views of its nature and extent. These include "Nile Craton", "Sahara Congo Craton", "Eastern Saharan Craton" and "Central Saharan Ghost Craton". This last term is because the older rocks are almost completely covered by recent sediments and desert sands, making geological analysis difficult.
The Svecofennian orogeny is a series of related orogenies that resulted in the formation of much of the continental crust in what is today Sweden and Finland plus some minor parts of Russia. The orogenies lasted from about 2000 to 1800 million years ago during the Paleoproterozoic Era. The resulting orogen is known as the Svecofennian orogen or Svecofennides. To the west and southwest the Svecofennian orogen limits with the generally younger Transscandinavian Igneous Belt. It is assumed that the westernmost fringes of the Svecofennian orogen have been reworked by the Sveconorwegian orogeny just as the western parts of the Transscandinavian Igneous Belt has. The Svecofennian orogeny involved the accretion of numerous island arcs in such manner that the pre-existing craton grew with this new material from what is today northeast to the southwest. The accretion of the island arcs was also related to two other processes that occurred in the same period; the formation of magma that then cooled to form igneous rocks and the metamorphism of rocks.
The Pampean orogeny was an orogeny active in the Cambrian in the western margin of the ancient landmass of Gondwana. The orogen's remains can now be observed in central Argentina, in particular at the Sierras de Córdoba and other parts of the eastern Sierras Pampeanas. It is uncertain if the orogeny involved at some point a continental collision. The Pampean orogen can be considered both part of the larger Terra Australis orogen and of the Brasiliano orogeny. The Pampean orogeny was succeeded by the Famatinian orogeny further west.
The Sunsás orogeny was an ancient orogeny active during the Late Paleoproterozoic and Mesoproterozoic and currently preserved as the Sunsás orogen in the Amazonian Craton in South America. About 85% of the belt is covered by Phanerozoic sediments. Among the remaining 15% of the orogen exposed at surface the best outcrops lies around the Bolivia-Brazil border. It is thought that the original orogen once spanned an area from Venezuela to Argentina and Paraguay. The western and southeastern fringes of the Sunsás orogen have been incorporated into the Andean orogeny and the Brasiliano orogeny respectively. The Sunsás orogeny was active during four separate phases:
The Aravalli Mountain Range is a northeast-southwest trending orogenic belt in the northwest part of India and is part of the Indian Shield that was formed from a series of cratonic collisions. The Aravalli Mountains consist of the Aravalli and Delhi fold belts, and are collectively known as the Aravalli-Delhi orogenic belt. The whole mountain range is about 700 km long. Unlike the much younger Himalayan section nearby, the Aravalli Mountains are believed much older and can be traced back to the Proterozoic Eon. They are arguably the oldest geological feature on Earth. The collision between the Bundelkhand craton and the Marwar craton is believed to be the primary mechanism for the development of the mountain range.
The geology of Brazil includes very ancient craton basement rock from the Precambrian overlain by sedimentary rocks and intruded by igneous activity, as well as impacted by the rifting of the Atlantic Ocean.
The Superior Craton is a stable crustal block covering Quebec, Ontario, and southeast Manitoba in Canada, and northern Minnesota in the United States. It is the biggest craton among those formed during the Archean period. A craton is a large part of the Earth's crust that has been stable and subjected to very little geological changes over a long time. The size of Superior Craton is about 1,572,000 km2. The craton underwent a series of events from 4.3 to 2.57 Ga. These events included the growth, drifting and deformation of both oceanic and continental crusts.
The Cornian orogeny was a small scale orogenic event between 2.0 and 1.86 billion years ago in the Proterozoic. At the time, the Gawler Craton in what is now Australia may have been experiencing passive margin conditions, given the rocks found in the Hutchison Group overlying the Miltalie Gneiss. The orogeny caused metamorphism and east-southeast striking rock fabrics. The event is mostly preserved east of the Kalinjala Shear Zone along with the Donington Suite intrusive rocks.
The Kararan orogeny was an orogenic event in the Gawler Craton of South Australia during the Proterozoic between 1.57 and 1.55 billion years ago which reworked rocks metamorphosed during the Kimban orogeny.
The geology of the Kimberley, a region of Western Australia, is a rock record of the early Proterozoic eon that includes tectonic plate collision, mountain-building (orogeny) and the joining (suturing) of the Kimberley and Northern Australia cratons, followed by sedimentary basin formation.